First, several studies demonstrated the lack of specificity of FC for IBD, and it is increased in colorectal cancer, gastroenteritis, irritable bowel syndrome, diverticulitis, food intolerance, and non-steroidal enteropathy as well.21 In our patient cohort, faecal PAI-1 demonstrated remarkable selectivity as it was elevated only in active IBD patients. Here, SERPINE1 is linked to irritable bowel syndrome.